Sydney's Spit Bridge opening times may be further restricted to help cope with growing traffic, NSW Road Minister Eric Roozendaal says.

Spit Bridge times 'may be restricted'

Sydney's Spit Bridge opening times may be further restricted to help cope with growing traffic, NSW Road Minister Eric Roozendaal says.

He was speaking following traffic chaos on Monday night caused by a fault on the bridge.

An electrical fault with a lifting mechanism left thousands of commuters stuck in northern Sydney suburbs because the bridge could not be lowered after the 7.30pm opening.

The bridge links the northern Sydney suburbs of Seaforth and Mosman, and is the main corridor from the city to the northern beaches.

Thousands of commuters were stranded, with traffic banked up for almost a kilometre in either direction.

The problem took the NSW Roads and Traffic Authority (RTA) two-and-a-half hours to fix.

Mr Roozendaal said the incident would trigger an RTA review of the bridge, with a possibility that opening times could be further restricted.

"There is no doubt the Spit Bridge is a problem and that's why we're looking at a full strategy to manage that corridor," Mr Roozendaal told reporters in Sydney.

"We have minimised the opening times for the bridge so there are no openings during the morning peak.

"I think it may be appropriate to review opening times for the evening.

"I think it is appropriate when you have an incident that does cause delays to a corridor that we go back and review it ... it may well mean we need to adjust the opening even more."

A working group set up to investigate improvements to the bridge had now completed its report, Mr Roozendaal said.

The working group was set up by Mr Roozendaal after the NSW government abandoned an election promise to widen the bridge.

It was charged with examining proposals such as fast-tracking new bus lanes, clearways on Military Road and reduced bridge opening times.

"That working group has completed its report and is now with the RTA's CEO, who will be reporting back to me," Mr Roozendaal said.

Mr Roozendaal said Monday night's mechanical problems on the Spit Bridge were rare.

"I am disappointed that we had an extended delay in the Spit Bridge and I've asked the RTA to review this incident fully to see if we can deal with these issues quicker next time and minimise the inconvenience," he said.

NSW Premier Morris Iemma also described the incident as "frustrating".

"Last night's incident was frustrating and obviously we apologise for the inconvenience that was caused," he told reporters.

"From the information that I have got, it was not the cause of anyone not doing something they should.

"It's frustrating that an electrical fault could do that."

Mr Iemma also denied that improving traffic flow on the bridge was delayed because the northern beaches were not marginal seats and were held by the Liberal Party.

"We don't determine the allocation of dollars for road works for infrastructure on where they sit on the electoral pendulum," he said.